In olden times, candling eggs was literally done with a candle. The purpose of candling is to shine a light through the egg so you can see what’s going on inside it. This old-fashioned candle process totally doesn’t work for me. The light just isn’t bright enough. I think I’d need a bonfire.
So I made a candling box.
How to make a candling box:
1 small cardboard box
Using a knife, cut a hole–approximately one inch in diameter–into a small cardboard box. Insert the light and cover the top with towels so the only light that escapes is through that small hole. Take the box into a dark room.
Hold the egg to be candled against the hole so that the light is blocked as much as possible except what shines through the egg. After incubating for one week, what you’re hoping to see is a dark spot surrounded by a spiderlike webbing of vessels. This means the embryo is developing correctly.
If it’s not developing correctly, you may see a thin ring, or blood ring, showing that the embryo has died, or a yolk shadow, which means either the embryo has died or the egg was never fertile to begin with. What I believe I’m seeing in my eggs is the yolk shadow.
After my trip to the chicken farm, I managed to screw up fast, within 24 hours, by overheating my eggs with sunlight coming through a window onto the incubator. It’s been seven days since I put these eggs in the incubator and I don’t see any signs of developing embryos in the eggs. I think I’m seeing yolk shadows rather than a blood ring because the eggs really never had a chance to develop at all since they were overheated so soon after incubation began. I’m pretty sure the eggs were fertile.
I’m already incubating a second batch!
And I didn’t throw out the eggs from the first batch yet. Princess found this concept too painful. I won’t keep them around forever because if they are bad, eventually they’ll explode, but I promised her I’d keep them a few more days, at least long enough to candle them again and to candle the second batch after they’ve incubated a week to compare.
Isn’t candling neat? What goes on inside an egg is sorta mysterious and secretive–and uncertain enough to be interesting!